This invention concerns cabinet structures having storage compartments or members such as drawers or racks and mounted for translational movement in the cabinet and more particularly, a stabilizing arrangement for such movable storage compartments in which there is a tendency of the member to be skewed in the plane of movement upon the application of transverse forces to the direction of movement.
In mounting a drawer or other member mounted for relative translational movement with respect to a support structure, the member is generally mounted for in and out movement in the cabinet along a fixed line of movement and some means is provided for controlling the lateral orientation of the member during its movement. This lateral guidance, in the plane of movement, is commonly achieved by drawer guides which limit the degree of skew or tilt of the drawer occurring due to sideward directed components of the drawer pulling force. Such guide surfaces must provide some clearance in order to provide free movement, which degree increases with the decreasing degree of precision of the guides, and accordingly some looseness may be perceived in the opening and closing of the drawer. Such looseness may also create an increase in the degree of opening and closing effoct required in that the skew may produce jamming or relatively tight frictional drag greatly increasing the effort required in opening or closing the drawer.
Similarly, the drawer mounting components may include guides in which the lifting of the drawer during its in and out movement is controlled, and similarly the clearance usually provided for free movement allows some degree of looseness.
If the drawer is relatively heavy, the weight loading of the drawer is sufficient to provide adequate vertical stability of the drawer. However, for unloaded lightweight drawer structures, such as in dishwasher racks, the looseness both laterally and vertically produces an objectional sensation of sloppiness in moving the drawer in and out of the supporting cabinetry and other structure. While precision mounting components could substantially eliminate such looseness, in many applications the cost of precision components would be prohibitive, such as in mass-produced appliances.
In most front-loading dishwashers, there is provided dishracks which are movable into and out of the interior of the dishwasher cabinet in order to enable loading of the dishware items. Such racks are typically supported by means of simple individually mounted plastic rollers or guides mounted on the dishrack on the interior of the cabinet.
Simple roller mounting arrangements are necessitated both in the interests of minimizing manufacturing costs and also due to the fact that the interior cabinet is subjected to the washing water spray. Such simple support arrangements however result in a tendency for the rack to be skewed slightly upon uneven application of the pulling forces, creating a feeling of objectionable looseness to the person manipulating the rack.
U.S. Pat. No. 3,323,853 discloses a torque equalizing arrangement in which an axle shaft is provided, supported on rollers bearing the weight of the drawer. The axle shaft has pinion gears secured at either end to the axle shaft in engagement with gear racks located on the underside of the drawer. The torsional interconnection of the pinion gears defeats the tendency to skew. This arrangement, while basically achieving the anti-skew effect, involves a relatively elaborate structure, i.e., the pinion gears and rack, which would add considerably to the cost of manufacture of the drawer.
In addition, the bottom-mounting of the axle would not be suitable in upper dishwasher rack applications as it would interfere with the cleaning action of the dishwasher spray.
The lightweight characteristic of such dishwasher racks tends to produce a certain vertical looseness in the movement of the rack as well, since the rollers are only lightly loaded, which would not be alleviated by the arrangement disclosed in U.S. Pat. No. 3,323,853.
Accordingly, it is an object of the present invention to provide a motion stabilizer arrangement for members mounted for relative translational movement with respect to a supporting structure such as drawers or dishwasher racks mounted for in and out movement in a cabinet.
It is a further object of the present invention to provide a motion stabilizer arrangement which is adaptable for the upper rack of a dishwasher.
It is yet another object of the present invention to provide a motion stabilization arrangement which also vertically stabilizes the member in its movement by preloading the member such that lightweight racks may thereby be vertically stabilized in their movement.